Wednesday, October 25, 2017

Cessna TR182 Turbo Skylane, N4707S, E & B Aero LLC: Fatal accident occurred September 05, 2015 near Midland International Air and Space Port (KMAF), Midland County, Texas

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Analysis

The commercial pilot took off from the airport in the airplane with three passengers on board. The pilot reported that, during the takeoff and while crossing the departure end of the runway, the engine began to lose power. The pilot managed to climb and level off the airplane about 40 ft above ground level. The airplane would not maintain altitude, so he conducted a wheels-up landing in a field. The passengers reported that, during the forced landing, the airplane struck a rock and stopped suddenly. The pilot sustained serious injuries and died 24 days after the accident.

Postaccident examination confirmed flight control continuity. An examination of the turbocharger revealed that the wastegate actuating cable was frayed and kinked at both ends. When the throttle was advanced, the cable bound. The bypass valve's actuator arm was corroded, and the bolt and nut used to fasten the actuator cable to the arm were seized and corroded. An examination of the single-driven dual magneto revealed that both sides had improper ignition timing. A subsequent examination revealed that the points were worn. During a bench test, the magneto operated normally. Because the engine was test run successfully with the wastegate cable, bypass valve actuator, and magneto in place, it is unlikely that they directly caused the partial loss of engine power. However, the role they might have played in the power loss could not be determined.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

The partial loss of engine power for reasons that could not be determined based on the available evidence.

Findings

Aircraft
Turbocharger - Damaged/degraded
Magneto/distributor - Fatigue/wear/corrosion

Not determined
Not determined - Unknown/Not determined (Cause)


The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Lubbock, Texas
Textron Aviation; Wichita, Kansas
Lycoming Engines; Arlington, Texas

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N4707S

NTSB Identification: CEN15LA404
14 CFR Part 91: General Aviation
Accident occurred Saturday, September 05, 2015 in Midland, TX
Aircraft: CESSNA TR182, registration: N4707S
Injuries: 1 Fatal, 3 Minor.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On September 5, 2015, about 1836 central daylight time, a Cessna TR182 airplane, N4707S, impacted terrain following a forced landing to a field near Midland, Texas. The pilot was seriously injured at the time of the accident, but succumbed to his injuries 24 days later. The three passengers were not injured. The airplane was substantially damaged. The airplane was registered to E & B Aero LLC and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal cross-country flight. Visual meteorological conditions prevailed at the time of the accident and no flight plan had been filed. The flight originated from Midland International Air & Space Port (MAF), Midland, Texas, and was en route to El Paso International Airport (ELP), El Paso, Texas.

The airplane departed from runway 16R at MAF, and proceeded south. The airport elevation was 2,872 ft mean sea level (msl). GPS data showed the airplane climbed to an altitude of 2,910 ft, where it leveled off. This occurred about one minute after takeoff and the airplane's recorded groundspeed was 58 kts. The airplane remained around this altitude for about 32 seconds before descending to the ground. The airplane's groundspeed while level was about 60 kts. During the descent to the ground, the airplane's airspeed decreased to about 50 kts.

The passengers on board the airplane said that right after takeoff the pilot experienced difficulties with the airplane. It was not developing power and it would not climb. The pilot elected to put the airplane down in a field rather than bring the airplane back around to land at MAF. The passengers said he did a good job controlling the airplane. During the forced landing in the field, the airplane struck a rock. The sudden stop resulted in the pilot sustaining a broken back. The passengers were able to get out of the airplane on their own.

In a postaccident interview with the FAA, the pilot told the inspector that the wastegate might not have opened. It was a problem the pilot experienced during a previous flight, during which he described that engine was running, but the manifold pressure "overboosted." Three days before the accident he had a repair station replace the manifold pressure gauge and bypass valve. The pilot stated that during the accident flight the airplane was configured with 10 degrees of flaps for takeoff and the mixture was full rich. During the takeoff, the engine was at full power and the airspeed increased to between 80 and 100 kts. As the airplane crossed the departure end of the runway, he realized that the manifold pressure was up and the rpms were low. He decided to continue the flight rather than land straight ahead. When he found that the airplane could not maintain altitude, he executed a wheels up forced landing in a field.

The airplane was located in grass field two miles south of the airport. An examination of the airplane at the scene showed substantial damage to the engine mounts and firewall. The airplane's lower cowling and nose gear doors were crushed upward. The fuselage, aft of the rear cabin at the baggage compartment, was bent downward. The main landing gear were crushed upward into their wheel wells. The propeller showed torsional bending, chordwise scratches and leading-edge nicks. One of the two propeller blades was bent and twisted aft under the nose cowling, and exhibited laterally running scrapes and material missing at the blade tip. Flight control continuity was confirmed. A portable GPS unit and an engine monitoring device were retained and sent to the NTSB Vehicle Recorders Laboratory for examination and data readout.

A review of the airplane's maintenance records showed it underwent an annual inspection on February 19, 2015. The airframe time at the inspection was 2,142.2 hours. Further review of the records showed that between July 29 and August 19, 2015, the turbocharger wastegate was checked, and it was found the pressure relief valve was not opening correctly to limit the manifold pressure. The valve was replaced and it functioned properly during a ground run of the engine. Also during the records review, it was discovered that a service bulletin, Lycoming Service Bulletin SB-643, had not been complied with.

The airplane was examined in Lancaster, Texas, on October 29-30, 2015. Examination of the engine showed continuity throughout. The single-drive dual magneto was tested for proper ignition timing. The left magneto was at 18-degrees before top center (BTC). The right magneto was at 16-degrees BTC. Proper ignition timing is 23-degrees BTC.

The turbocharger waste gate actuating cable was frayed and kinked at both ends. When the throttle was advanced, the cable binded. The actuator arm on the bypass valve was corroded and the bolt and nut used to fasten the actuator cable to the arm was seized and corroded.

The engine and airplane fuselage was secured to a trailer and using the on-board battery and engine starter, the engine was started and run to 1,400 rpm when the number 5 top spark plug shorted due to lead fowling. The spark plug was replaced and the engine operated to full power (2,400 rpm). The power was then reduced to 1,800 rpm and an ignition test was performed. Both magnetos dropped about 300 rpm. The operating limitation is a drop no lower than 150 rpm on each magneto. The turbocharger operated normally during the test run and manifold pressure achieved 31.5 inches of mercury at full power.

Following the engine run, the magneto was removed and disassembled for inspection. The points were excessively worn. The magneto was reassembled and tested and operated from 0 to 3,000 rpm with no defects.

The engine monitoring device was examined on November 20, 2015. The device was a panel mounted gauge that allowed the pilot to monitor and record up to 24 parameters related to engine operations. The data extracted included 15 sessions from May 23 to the accident flight. Data extracted from the accident flight revealed:

The engine monitor began recording at engine start. A plot of the data for the accident flight showed that about 420 seconds, EGT, manifold pressure (MAP) and engine rpm began to climb. RPM increased from 1,250 to about 1,750, MAP rose from 18 inches to 20 inches, and EGTs rose from about 1,200 to 1,300 degrees F.

About 540 seconds, these parameters increased again with EGT exceeding 1,400-degrees F, MAP rising to 31 inches, and RPM to 2,500. This would have occurred about the time the airplane took off.

At 700 seconds, engine RPM decreased to zero and EGT decreased to about 1,000 degrees F. MAP was about 30 inches. All recorded data ended 20 seconds later.

The pilot died on September 29, 2015. The El Paso County, Texas, Medical Examiner cited the cause of death as complications of multiple blunt injuries.

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